Mobile terminal and method of controlling the same

ABSTRACT

A mobile terminal and method of controlling the same, each that can integrally move between an infrastructure network and an ad hoc network. The mobile terminal can interconnect to an infrastructure network and an ad hoc network while moving. In an address management process, a connection network identification process, and a destination address capture process which are needed to establish communications with the terminal connected to a network, an infrastructure network connection procedure is integrated with an ad hoc network connection procedure. The integrated configuration consists of an ad hoc/ infrastructure network address management means, an ad hoc/ infrastructure integration move management means, an ad hoc/ infrastructure network integration destination address capture means. In each process, it is identified whether or not the mobile terminal is connected to an ad hoc network or infrastructure network, so that the procedure corresponding to the connected network is used.

BACKGROUND OF THE INVENTION

The present invention relates to a mobile terminal that can integrallymove between an infrastructure network and an ad hoc network and to amethod of controlling the same.

An infrastructure network in which networks such as internets areinterconnected via a relay node such as a router as well as an ad hocnetwork which has no relay node and is a network temporarily configuredof only terminals are well known as aspects of a network.

In order to establish communications by connecting a mobile terminal toa network, the mobile terminal must have (1) a terminal address used ina network to be connected, or a network address of the network itselfand (2) an opposite communication party's address.

With respect to the item (1), the dynamic host configuration protocol,DHCP, (for example, refer to Douglas E. Comer, “Internetworking withTCP/IP Volume I principles, protocols and architecture”, Third edition,1995, Prentice-Hall, Inc.) is well known with an internet being anexample of an infrastructure network. Moreover, with respect to the item(2), the domain name system, DNS, (for example, refer to Douglas E.Comer, “Internetworking with TCP/IP Volume I principles, protocols andarchitecture”, Third edition, 1995, Prentice-Hall, Inc.) is well known.In the DHCP, a DHCP server is set up that holds a terminal address orinfrastructure network address to be allocated to a terminal. Necessaryvalues such as terminal or network addresses for connection arerequested to the DHCP server when a terminal is connected to a network.The DHCP server provides parameters to the terminal without troubles dueto duplicate terminal addresses, based on the request from the terminal.FIG. 15 depicts such an operation. When the terminal 1 and the terminal2 are connected to a network, they respectively broadcast DHCP Requestscontaining desired information. FIG. 15 shows an example in which theterminals 1 and 2 request a terminal address. In response to the DHCPRequest message, the DHCP server transmits a DHCP ACK message containingsupply information to the request sources. In FIG. 15, the DHCP servertransmits two DHCP ACK messages, one containing an address 1 and theother containing an address 2, to avoid overlapping of a terminaladdress at the terminals 1 and 2.

In the internet, the DNS (Domian Name System) is used to detect thecorrespondence between the terminal name of a terminal and the terminaladdress. The DNS introduces a DNS server that manages thecorrespondences between the terminal's names of terminals to be managedand the terminal addresses and predetermines the procedure of makinginquiries from a terminal to the DNS server and the procedure of makinginquiries between servers. In most cases, the address of the DNS servermanaging a terminal is set to the terminal itself. FIG. 16 depicts thecase where the terminal 1 detects the terminal address of the terminal2. The terminal 1 transmits a DNS Query message requesting the terminaladdress of the terminal 2 to the DNS server (the DNS server 1 in FIG.16) registered. The DNS server 1 inquires the DNS server (the DNS server2 in FIG. 16) managing the terminal address of the terminal 2. Then theDNS server 1 notifies the terminal 1 of the address 2 (DNS Replymessage) when obtaining the terminal address of the terminal 2 (address2).

The ad hoc network is configured of only terminals and does not have aserver such as DHCP server or DNS server used in the infrastructurenetwork. For this reason, even if the same procedure as that in theinfrastructure network are used, communications cannot be accomplishedby connecting the terminal to an ad hoc network. In order to accomplishcommunications according to the same procedure as that in theinfrastructure network, a server function may be added to one ofterminals connected to an ad hoc network. However, since this approachrequires a special terminal with a server function, it is considerablypoor in versatility. In order to improve the versatility, a proceduredifferent from that in the infrastructure network may be defined in thead hoc network so that the procedure can be selectively used accordingto an ad hoc network or infrastructure network to be connected. However,in the case of this procedure, the terminal must be reset when it movesbetween an ad hoc network and an infrastructure network according to theprocedure for an infrastructure network and the procedure for an ad hocnetwork to be introduced thereto.

SUMMARY OF THE INVENTION

The objective of the present invention is to solve the above-mentionedtasks.

Moreover, the objective of the invention is to provide a mobile terminalthat can integrally move between an infrastructure network and an ad hocnetwork.

Furthermore, another objective of the present invention is to provide amobile terminal control method that enables information regardingcommunications and connection to an ad hoc network to be effectivelyprovided between mobile terminals in an ad hoc network.

The objective of the present invention is achieved by a mobile terminalthat can be connected in a mobile mode between an infrastructure networkand an ad hoc network, the infrastructure network being a permanentnetwork interconnected via a relay node, the ad hoc network being atemporary network formed of only plural terminals, the infrastructurenetwork having plural mobile terminals, relay nodes, and a server whichprovides information needed for connection of mobile terminals; andwherein an infrastructure network connection procedure and an ad hocnetwork connection procedure are configured in an integrated mode in anaddress management process, a connection network identification processand a destination address capture process which are needed when saidmobile terminal is connected to a network to establish communications;wherein each process including steps of identifying whether a network towhich the mobile terminal is connected is an ad hoc network orinfrastructure network and then using a procedure corresponding to theconnected network.

Moreover, a mobile terminal that can be connected in a mobile modebetween an infrastructure network and an ad hoc network, theinfrastructure network being a permanent network interconnected via arelay node, the ad hoc network being a temporary network formed of onlyplural terminals, the infrastructure network having plural mobileterminals, relay nodes, and a server which provides information neededfor connection of mobile terminals, the mobile terminal comprisesreceive packet input means for inputting as a receive packet a packettransmitted onto a communication medium configuring a network to beconnected; transmission packet output means for transmitting atransmission packet onto the communication medium; means for inputtingan opposite communciation party's name of the mobile terminal itself;means for outputting a destination address corresponding to the oppositecommunication party's name; address management means for receiving thereceive signal, for identifying whether or not the network to beconnected is the infrastructure network or ad hoc network, and fortransmitting the transmission packet which captures and manages anaddress used in the network; destination address capture means forreceiving the receive signal, for identifying whether or not the networkto be connected is an infrastructure network an ad hoc network, foroutputting the transmission packet to capture the destination addresscorresponding to the opposite communication party's name, and forobtaining a destination address of the opposite communication party'sname; and move management means for receiving the receive packet andoutputting the transmission packet to manage whether or not the movableterminal itself has moved from the network to be connected to anothernetwork.

In the mobile terminal according to the present invention, the addressmanagement means comprises ad hoc/ infrastructure network identificationmeans for identifying whether or not a network to be connected by themobile terminal itself is the infrastructure network or the ad hocnetwork in response to the receive packet, for outputting a networkidentification signal representing a network to which a network to beconnected by the mobile terminal itself is connected, for outputting aninfrastructure network connection signal when the network to beconnected is the infrastructure network, and for outputting an ad hocnetwork connection signal when the network to be connected is the ad hocnetwork; infrastructure network address management means for receivingthe receive packet and the infrastructure network connection signal, foroutputting necessary transmission data as the transmission packet, andfor managing an address used by the mobile terminal itself when anetwork to be connected by the mobile terminal itself is aninfrastructure network; ad hoc network address management means forreceiving the receive packet and the ad hoc network connection signal,for outputting necessary data as the transmission packet, and formanaging an address used by the mobile terminal itself when the networkto be connected by the mobile terminal itself is an ad hoc network; anda switch for receiving the network identification signal, thetransmission packet from the infrastructure network address managementmeans, and the transmission packet from the ad hoc network addressmanagement means, for selectively outputting the transmission packetfrom the infrastructure network address management means by the networkidentification signal when a network in a connection state to the mobileterminal itself is an infrastructure network, and for selectivelyoutputting the transmission packet from the ad hoc network addressmanagement means when the network in a connection state is an ad hocnetwork.

In the mobile terminal according to the present invention, the ad hoc/infrastructure network identification means comprises infrastructurenetwork advertisement message receive means for receiving aninfrastructure network advertisement message containing a networkaddress of an infrastructure in response to the receive packet and foroutputting an infrastructure network advertisement message receivesignal representing that the infrastructure network advertisementmessage has been received when the infrastructure network advertisementmessage contains a network address equal to a network address of anetwork connected to the mobile terminal itself; ad hoc networkadvertisement message receive means for receiving an ad hoc networkadvertisement message containing a network address of an ad hoc networkin response to the receive packet and for outputting an ad hoc networkadvertisement message receive signal representing that the ad hocnetwork advertisement message has been received when the ad hoc networkadvertisement message contains a network address equal to a networkaddress of a network connected to the mobile terminal itself; a firstcounter for performing a reset operation by receiving the ad hoc networkadvertisement message receive signal and a reset signal, counting thenumber of ad hoc network advertisement messages, and outputting thenumber of the ad hoc network advertisement messages every time the resetsignal is received; a second counter for performing a reset operation byreceiving the infrastructure network advertisement message receivesignal and the reset signal, counting the number of infrastructurenetwork advertisement messages, and outputting the number of theinfrastructure network advertisement messages every time the resetsignal is received; a timer for measuring a predetermined period of timeand then outputting the rest signal when a time-out occurs; an adder foradding an output from the first counter and an output from the secondcounter; a first comparator for comparing the output from the firstcounter with zero to obtain a result, outputting the result as theinfrastructure network connection signal, and outputting data whichcreates the network identification signal; a second comparator forcomparing the output from the second counter with zero to obtain aresult and outputting the result to the decoder which creates thenetwork identification signal and to an encoder which creates the ad hocnetwork connection signal; and a third comparator for comparing theoutput from the adder with zero to obtain a result and outputting theresult to the decoder which creates the network identification signaland to an encoder which creates the ad hoc network connection signal;the decoder receiving signals from the first, the second, and the thirdcomparators to create an infrastructure or ad hoc network connectionsignal; the encoder receiving signals from the second and the thirdcomparators and then encoding the ad hoc network connection signalrepresenting whether or not the mobile terminal itself configures a newad hoc network or the mobile terminal itself is connected to an existingad hoc network, based on the input signal.

In the mobile terminal according to the present invention, the ad hocnetwork address management means comprises ad hoc network/ networkaddress management means for receiving the receive packet and the ad hocnetwork connection signal, outputting a message requesting a networkaddress containing a network address used in a new ad hoc network when anew ad hoc network is configured for connection as the transmissionpacket and a message representing a spent network address when the adhoc network/ network address request message containing the spentnetwork address in an ad hoc network connected by the mobile terminalitself has been received, capturing a network address of an ad hocnetwork to which the mobile terminal itself is connected, based on thereceive packet, outputting a network address captured signalrepresenting that the captured network address and the network addresshave been captured, and managing the captured network address not to beused in an overlap mode; and an hoc network/ terminal address managementmeans for receiving the receive packet, the ad hoc network connectionsignal, the captured network address, and the network address capturedsignal, outputting as the transmission packet a message requesting aterminal address list being used in the ad hoc network when the mobileterminal is connected to an existing ad hoc network and a messagecontaining the terminal address list held by the mobile terminal itselfin response to the address list requesting message, capturing a terminaladdress used in ah hoc network to be connected by the mobile terminalitself, based on the receive packet and the ad hoc network connectionsignal, and acknowledging a terminal address to be used in the ad hocnetwork connected by the mobile terminal itself.

In the mobile terminal according to the present invention, thedestination address capture means comprises ad hoc/ infrastructurenetwork identification means for receiving the receive packet,identifying whether or not a network to which the mobile terminal isconnected is the infrastructure network or the ad hoc network,outputting a network identification signal representing a network to beconnected to a network connected by the mobile terminal, outputting aninfrastructure network connection signal when the network to beconnected is the infrastructure network, and outputting an ad hocnetwork connection signal when the network to be connected is the ad hocnetwork; a first switch for receiving the name of the oppositecommunication party's name of the mobile terminal itself and the networkidentification signal and selecting a destination of the oppositecommunication party's name based on the network identification signal;infrastructure network/ destination address capture means for receivingthe infrastructure network connection signal and the oppositecommunication party's name, transmitting a message requesting a terminaladdress corresponding to the communication opponent's name, detecting amessage containing a terminal address corresponding to the oppositecommunication party's name from the receive packet, and outputting theterminal address corresponding to the opposite communication party'sname; ad hoc network/ destination address capture means for receivingthe ad hoc network connection signal and the opposite communicationparty's name, transmitting a message requesting a terminal addresscorresponding to the opposite communication party's name, detecting amessage containing a terminal address corresponding to the oppositecommunication party's name from the receive packet, and outputting theterminal address corresponding to the opposite communication party'sname; a second witch for selectively outputting a terminal addresscorresponding to the opposite communication party's name captured by theinfrastructure network/ destination address capture means and a terminaladdress corresponding to the opposite communication party's namecaptured by the ad hoc network/ destination address capture means, basedon the network identification signal; and a third switch for selectivelytransmitting a message requesting a terminal address corresponding tothe opposite communication party's name captured by the infrastructurenetwork/ destination address capture means and a message requesting aterminal address corresponding to the opposite communication party'sname captured by the ad hoc/ destination address capture means, based onthe network identification signal.

In the mobile terminal according to the present invention, the ad hocnetwork/ destination address capture means comprises destinationterminal address detection means for receiving the networkidentification signal, starting up when a connection network of themobile terminal itself is an ad hoc network, receiving the receivepacket and the ooposite communication party's name, outputting theterminal address of the opposite communication party's name by detectinga destination address message containing correspondence relationshipsbetween the opposite communication party's name and the oppositecommunication party's terminal address from the receive packet, andoutputting a terminal address capture signal of the oppositecommunication party; destination terminal address request message outputmeans for receiving the opposite communication party's name,broadcasting as the transmission packet a message requesting thecorrespondence relationship between the opposite communication party'sname and the opposite communication party's terminal to a communicationmedium in which a connection network of the mobile terminal itselfconfigures an ad hoc network, and outputting a timer start-up signal; atimer for starting measuring a predetermined period of time in responseto the timer start-up signal, ceasing measurement of the predeterminedperiod of time when a terminal address capture signal of the oppositecommunication party is received during measuring the predeterminedperiod of time, and outputting a time-out signal representing a time-outwhen the measurement of the predetermined period of time ends; terminaladdress non-capture detection means for outputting a terminal addressnon-capture signal representing that a terminal address corresponding tothe opposite communication party's name cannot be captured, when thetime-out signal is received; a control circuit for outputting a switchcontrol pulse that selects the terminal address non-capture signal whenthe time-out signal is input and selects a terminal address capturesignal of the opposite communication party when a terminal addresscapture signal of the opposite communication party is input; a switchfor selectively outputting the terminal address non-capture signal orthe terminal address capture signal of the opposite communication party,based on the switch control pulse; destination terminal address requestmessage detection means for detecting the destination terminal addressrequest message in response to the receive packet and then outputtingthe destination address message transmission request signal when thedestination terminal address request message requests a terminal addressto the name of the mobile terminal itself; and destination terminaladdress message transmission means for broadcasting as the transmissionpacket the destination terminal address message containing its ownterminal address to a communication medium in which a connection networkof the mobile terminal configures an ad hoc network, when thedestination address message message transmission request signal isinput.

In the mobile terminal according to the present invention, the ad hoc/infrastructure network identification means comprises infrastructurenetwork advertisement message receive means for receiving aninfrastructure network advertisement message containing a networkaddress of an infrastructure network in response to the receive packet,and outputting an infrastructure network advertisement message receivesignal representing that the infrastructure network advertisementmessage has been received when the infrastructure network advertisementmessage contains a network address equal to a network address of anetwork connected by the mobile terminal itself; ad hoc networkadvertisement receive means for receiving an ad hoc networkadvertisement message containing a network address of an ad hoc networkin response to the receive packet, and outputting an ad hoc networkadvertisement message receive signal representing that the ad hocnetwork advertisement message has been received when the ad hoc networkadvertisement message contains a network address equal to a networkaddress of a network connected by the mobile terminal itself; a firstcounter for performing a reset operation by receiving the ad hoc networkadvertisement message receive signal and a reset signal, counting thenumber of the ad hoc network advertisement messages, and outputting thenumber of the ad hoc network advertisement messages every time the resetsignal is input; a second counter for performing a reset operation byreceiving the infrastructure network advertisement message receivesignal and a reset signal, counting the number of the infrastructurenetwork advertisement messages, and outputting the number of theinfrastructure network advertisement messages every time the resetsignal is input; a timer for measuring a predetermined period of timeand outputting the reset signal when a time-out occurs; a firstcomparator for comparing an output of the first counter with zero todetermine a comparison result, and outputting the comparison result asthe infrastructure network connection signal to the decoder that createsthe network identification signal; and a second comparator for comparingan output of the second counter with zero to determine a comparisonresult, and outputting the comparison result as the ad hoc networkconnection signal to the decoder that creates the network identificationsignal; wherein the decoder that creates the network identificationsignal receives the infrastructure connection signal from the firstcounter and the ad hoc network connection signal from the secondcounter.

In the mobile terminal according to the present invention, the mobilemanagement means comprises network advertisement request messagetransmission means for detecting the infrastructure networkadvertisement message or the ad hoc network advertisement messagecontaining a network address of a network to which the mobile terminalis connected, in response to the receive packet, detecting that themobile terminal has been moved to a different network when theinfrastructure network advertisement message or the ad hoc networkadvertisement message cannot be received for a predetermined period oftime, and transmitting the infrastructure network advertisement messageor the ad hoc network advertisement request message requesting thenetwork address of the network; and ad hoc network advertisement meansfor receiving the receive packet when a network to which the mobileterminal is connected is an ad hoc network, and transmitting the ad hocnetwork advertisement message representing the presence of the ad hocnetwork in cooperation with another mobile terminal connected to the adhoc network.

In the mobile terminal according to the present invention, the networkadvertisement request message transmission means comprisesinfrastructure network advertisement message receive means for receivingan infrastructure network advertisement message containing a networkaddress of an infrastructure network in response to the receive packet,and outputting an infrastructure network advertisement message receivesignal representing that the infrastructure network advertisementmessage has been received when the infrastructure network advertisementmessage contains a network address equal to the network address of anetwork to which the mobile terminal itself is connected; ad hoc networkadvertisement message receiving means for receiving an ad hoc networkadvertisement message containing a network address of an ad hoc networkin response to the receive packet, and for outputting an ad hoc networkadvertisement message receive signal representing that the ad hocnetwork advertisement message has been received when the ad hoc networkadvertisement message contains a network address equal to a networkaddress of a network to which the mobile terminal itself is connected; afirst counter for performing a reset operation by receiving the ad hocnetwork advertisement message receive signal and a reset signal,counting the number of ad hoc network advertisement messages, andoutputting the number of the ad hoc network advertisement messages everytime the reset signal is received; a second counter for performing areset operation by receiving the infrastructure network advertisementmessage receive signal and the reset signal, counting the number ofinfrastructure network advertisement messages, and outputting the numberof the infrastructure network advertisement messages every time saidreset signal is received; a timer for measuring a predetermined periodof time and then outputting the rest signal when a time-out occurs; anadder for adding an output from the first counter and an output from thesecond counter; a comparator for comparing the output from the adderwith zero to obtain a result, and outputting an advertisement messagenon-receive signal when the result equals zero; infrastructure networkadvertisement request message transmission means for broadcasting theinfrastructure network advertisement request message onto acommunication medium used by the mobile terminal itself when theadvertisement message non-receive signal is received; and ad hoc networkadvertisement request message transmission means for broadcasting the adhoc network advertisement request message onto the communication mediumused by the mobile terminal itself when said advertisement messagenon-receive signal is received.

Moreover, according to the present invention, a method of controlling amovable terminal, comprises the step of providing information to a firstmobile terminal connected to an ad hoc network being a temporary networkconfigured of only plural terminals, wherein another mobile terminalstarts up a random timer in response to an information request from amobile terminal; wherein the random timer allows only a terminal whichhas first occurred a time-out to supply information.

Furthermore, according to the present invention, a mobile terminalcontrolling method including a procedure of providing information to amobile terminal, the mobile terminal being connected to an ad hocnetwork being a temporary network configured of only plural terminals,comprises the steps of broadcasting an information requesting message toall mobile terminals connected to the ad hoc network by means of a firstmobile terminal connected to an ad hoc network; starting up the randomtimer by means of each of the mobile terminals configuring the ad hocnetwork which receives the information requesting message, the randomtimer measuring a random time; broadcasting information supply messagecorresponding to the information requesting message to all mobileterminals connected to the ad hoc network by means of a mobile terminalin which time-out of the random timer has occurred among mobileterminals which have started up the random timer; and ceasing the randomtimer when each of the mobile terminals which have started up the randomtimer receives the information supply message and then stopping theinformation supply message from being transmitted.

Moreover, a method of controlling a mobile terminal, comprises the stepof providing information from a terminal with a shortest ad hoc networkconnection time when information is provided to a first mobile terminalconnected to said ad hoc network being a temporary network configured ofonly plural terminals.

Furthermore, according to the present invention, a mobile terminalcontrolling method including a procedure of providing information to amobile terminal, the mobile terminal being connected to an ad hocnetwork being a temporary network configured of only plural terminals,comprises the steps of broadcasting an information request message toall mobile terminals connected to an ad hoc network by means of a firstmobile terminal connected to the ad hoc network; determining an ad hocnetwork connection time based on a time connected to the ad hoc networkand a time at which the information requesting message has beenreceived, by means of each of mobile terminals configuring the ad hocnetwork which has received the information request message; starting upa timer that measures a time according to a period of time for which amobile terminal is connected to the ad hoc network; and broadcasting aresponse message corresponding to the information requesting messagewhen time-out of the timer has occurred, ceasing the timer; and haltingthe timer when a response message is received to the informationrequesting message during an operation of the timer.

According to the first aspect of the present invention, the mobileterminal can move between an infrastructure network and an ad hocnetwork without performing a reset operation.

According to the second aspect of the present invention, the mobileterminal control method can prevent information to be provided in anoverlap state.

Moreover, according to the third aspect of the present invention, themobile terminal control method can provide latest information andprevent information to be provided in an overlap state.

BRIEF DESCRIPTION OF THE DRAWINGS

This and other objects, features and advantages of the present inventionwill become more apparent upon a reading of the following detaileddescription and drawings, in which:

FIG. 1 is a block diagram illustrating the main configuration of amobile terminal according to the first aspect of the present invention;

FIG. 2 is a block diagram illustrating the configuration of the ad hocNW integration NW advertisement means in the mobile terminal accordingto the present invention;

FIG. 3 is a block diagram illustrating the configuration of the ad hoc/infrastructure NW integration NW advertisement request means in FIG. 1;

FIG. 4 is a block diagram illustrating the configuration of the ad hoc/infrastructure NW integration destination address capture means in FIG.1;

FIG. 5 is a block diagram illustrating the configuration of the ad hocNW destination address capture means in FIG. 4;

FIG. 6 is a block diagram illustrating the configuration of the ad hoc/infrastructure NW identification means 65 in FIG. 4;

FIG. 7 is a block diagram illustrating the configuration of the ad hoc/infrastructure NW integration address management means in FIG. 1;

FIG. 8 is a block diagram illustrating the configuration of the ad hoc/infrastructure NW identification means in FIG. 7;

FIG. 9 is a block diagram illustrating the configuration of the ad hocNW address management means in FIG. 7;

FIG. 10 is a block diagram illustrating the configuration of the ad hocNW/ network address management means in FIG. 9;

FIG. 11 is a block diagram illustrating the configuration of the ad hocNW/ network address capture means in FIG. 10;

FIG. 12 is a block diagram illustrating the configuration of the ad hocNW/ terminal address management means in FIG. 9;

FIG. 13 is a block diagram illustrating the configuration of the ad hocNW/ terminal address capture means in FIG. 12;

FIG. 14 is a block diagram illustrating the configuration of the ad hocNW/ terminal address list transmission means in FIG. 12;

FIG. 15 is a diagram illustrating the address capture procedure in aconventional infrastructure network; and

FIG. 16 is a diagram illustrating the destination terminal addresscapture procedure in a conventional infrastructure network.

DESCRIPTION OF THE EMBODIMENTS

The mobile terminal and the method of controlling the same according tothe present invention will be described below by referring to theattached drawings.

FIG. 1 illustrates the main configuration of the mobile terminalaccording to a first aspect of the present invention. Referring to FIG.1, numeral 40 and 46 represent input terminals; 41 and 47 representoutput terminals; 42 represents ad hoc network advertisement means; 43represents ad hoc/ infrastructure network integration advertisementrequest means; 44 represents ad hoc/ infrastructure network destinationaddress capture means; 45 represents ad hoc/ infrastructure networkintegration address management means; and 48 represents ad hoc/infrastructure integration move management means. Packets oncommunication medium for the mobile terminal are input as receivepackets via the input terminal 40. The packets are input to the ad hoc/infrastructure integration move management means 48, the ad hoc/infrastructure network integration advertisement request means 43, thead hoc/ infrastructure network integration destination address capturemeans 44, and the ad hoc/ infrastructure network integration addressmanagement means 45 via the input terminal 40. The above-mentionedsystem transmits necessary packets to be processed to the communicationmedium connected via the output terminal 41, judged whether or not anetwork connected to the mobile terminal is an ad hoc network orinfrastructure network, using receive packets, and implements addresscontrol necessary for network connection control of the mobile terminal,capture of a destination terminal address necessary for communicationcontrol, and move control of the mobile terminal. The ad hoc/infrastructure network integration destination address capture means 44outputs either a destination terminal address corresponding to adestination terminal's name input from the input terminal 46 orinformation regarding a terminal corresponding to an input destinationterminal's name not connected to the network, to the output terminal 47.The ad hoc/ infrastructure integration move management means 48 consistsof ad hoc/ infrastructure network integration network networkadvertisement request means 43 for requesting both an ad hoc networkadvertisement message containing a network address of ad hoc network andan infrastructure network advertisement message containing a networkaddress of an infrastructure network; and ad hoc network advertisementmeans 42 for transmitting ad hoc network advertisement message toadvertise the presence of an ad hoc network.

Referring to FIG. 1, the ad hoc network advertisement means 42 can beconfigured, for example, as shown in FIG. 2. Referring to FIG. 2,numeral 40 represents an input terminal; 251 represents ad hoc networkadvertisement message detection means; 252 represents ad hoc networkadvertisement request message detection means; 253 and 257 represent alogical sum arithmetic circuit; 254 represents a fixed timer; 255represents a random timer; 256 represents ad hoc network advertisementtransmission means; and 41 represents an output terminal. In aninfrastructure network, as shown by “C. perkins, “IP Mobility Support”,Request for Comment: 2002, RFC2002, October 1996, a mobile agent whichexists in an infrastructure network periodically broadcasts an agentadvertisement message being information containing addresses of themobility agent itself and the number of bits (net mask) used as anetwork address among the addresses. By receiving the message, themobile terminal detects move between infrastructure networks to beconnected. The mobile terminal on an infrastructure network can send anagent solicitation message to request agent advertisement messagebroadcasting. The mobile agent sends an agent advertisement message inresponse to the agent advertisement request message. In this embodiment,an agent advertisement message is called an infrastructure networkadvertisement message while an agent solicitation message is called aninfrastructure network advertisement request message.

In contrast, since there is no node functioning as a server such as amobility agent in the ad hoc network, a mobile terminal itself sends anad hoc network advertisement message containing network addresses in thead hoc network connected thereto and, if required, an ad hoc networkadvertisement message. The ad hoc network integration networkadvertisement means 42 controls a ad hoc network advertisement messagein the mobile terminal. The ad hoc network integration networkadvertisement means 42 controls transmission of an ad hoc networkadvertisement message using the method of controlling a mobile terminalaccording to the second aspect of the present invention. The ad hocnetwork advertisement message detection means 251 receives a receivepacket input via the input terminal 40 and then detects an ad hocnetwork advertisement message. The ad hoc network advertisement requestmessage detection means 252 receives a receive packet input via theinput terminal 40 and then detects an ad hoc network advertisementrequest message. The ad hoc network advertisement message detectionmeans 251 outputs an ad hoc network advertisement message detectionpulse to the logical sum arithmetic circuit 257 and outputs a randomtimer halt pulse to the random timer 255. The ad hoc network requestmessage detection means 252 outputs an ad hoc network advertisementrequest message receive pulse to the logical sum arithmetic circuit 253.The logical sum arithmetic circuit 257 receives an ad hoc networkadvertisement message detection pulse as well as a random timer time-outpulse output out of the random timer 255 and then outputs as a fixedtimer activation pulse the resultant logical sum to the fixed timer 254.The fixed timer 254 is reset every time the fixed timer start-up pulseis input. The fixed timer 254 measures a predetermined period of timeand then outputs a fixed timer time-out pulse to the logical sumarithmetic circuit 253 when a time-out occurs. The logical sumarithmetic circuit 253 receives an ad hoc network advertisement requestmessage receive pulse and a fixed timer time-out pulse and then outputsas a random timer start-up signal the resultant logical sum to therandom timer 254. The random timer 254 starts measuring the time to berandomly set every time being started up in response to the random timerstart-up pulse. The random timer 254 is reset every time the randomtimer halt pulse is input. When the random timer 254 becomes time-out,it outputs the random timer time-out pulse to the ad hoc networkadvertisement message transmission means 256 and the logical sumarithmetic circuit 257. The ad hoc network advertisement transmissionmeans 256 starts up every time the random timer time-out pulse is inputand then configures the ad hoc network advertisement message as abroadcast packet, thus outputting it via the output terminal 41.

In FIG. 1, the ad hoc/ infrastructure network integration networkadvertisement request means 43 can be configured as shown in FIG. 3.Referring to FIG. 3, numeral 0 represents an input terminal; 41represents an output terminal; 25 represents infrastructure networkadvertisement message receive means; 26 represents ad hoc networkadvertisement message receive means; 27 a and 27 b represent counters;34 represents a timer; 33 represents an adder; 29 represents acomparator; 50 represents infrastructure network advertisement requestmessage transmission means; 51 represents ad hoc network advertisementrequest message transmission means; and 52 represents a transmissionqueue. A packet is input to the infrastructure network advertisementrequest message transmission means 25 and the ad hoc networkadvertisement message receive means 26 via the input terminal 40. Theinfrastructure network advertisement message receive means 25 outputs apulse to the counter 27 a every time it detects an infrastructurenetwork advertisement message based on the input packet. The ad hocnetwork advertisement message receive means 26 outputs a pulse to thecounter 27 b every time it detects an ad hoc network advertisementmessage based on the input packet. Each of the counters 27 a and 27 bcounts up the number of input pulses. In response to a reset pulse fromthe timer 34, the counters 27 a and 27 b output respective count-upvalues to the adder 33. The timer 34 measures a predetermined period oftime and then sends a reset pulse to the counters 27 a and 27 b when thetime-out occurs while starting up. The adder 33 adds the output from thecounter 27 a with the output from the counter 27 b and then outputs thesum to the comparator 29. The comparator 29 compares the output from thecomparator with zero and then outputs a pulse representing zero or otherstatus to the infrastructure network advertisement request messagetransmission means 50 and the ad hoc network advertisement requestmessage transmission means 51. When the input pulse indicates zero, eachof the infrastructure network advertisement request message transmissionmeans 50 and the ad hoc network advertisement request messagetransmission means 51 judges that the mobile terminal has moved and thenoutputs a broadcast packet configured of an infrastructure networkadvertisement request message and an ad hoc network advertisementrequest message to the transmission queue 52 to capture the networkafter movement. The transmission queue 52 transmits as a broadcastpacket the infrastructure network advertisement request message and anad hoc network advertisement request message onto the communicationmedium via the output terminal 41.

The ad hoc/ infrastructure network integration destination addresscapture means shown in FIG. 1 can be configured as shown in FIG. 4. InFIG. 4, numerals 40 and 46 represent input terminals; 41 and 47represent output terminals; 64 represents ad hoc network destinationaddress capture means; 66 represents infrastructure network destinationaddress capture means; 65 represents ad hoc/ infrastructure networkdestination address capture means; and 61 to 63 represent switches. Thead hoc/ infrastructure network identification means 65 identifieswhether or not the network connected to the mobile terminal is an ad hocnetwork or infrastructure network by the packet input via the inputterminal 40. When the mobile terminal is connected to the ad hocnetwork, the ad hoc/ infrastructure network identification means 65controls the switches 61 and 63 to select the output from the ad hocnetwork destination address capture means 64. while it starts up the adhoc network destination address capture means 64. When the mobileterminal is connected to the infrastructure network, . . . The ad hocnetwork destination address capture means 64 and the infrastructurenetwork destination address capture means 66 receive a destinationterminal name from the input terminal 64 and then transmit a destinationterminal address request message onto the communication medium via theoutput terminal 41. The infrastructure network destination addresscapture means 66 also receives a receive packet from the input terminal40 and a destination terminal address response message responded to thetransmitted destination terminal request message and then outputs theresult to the output terminal 47. The destination terminal addressresponse message contains a requested destination terminal name and adestination terminal address.

The ad hoc network destination address capture means 64 shown in FIG. 4can be configured as shown in FIG. 5. Referring to FIG. 5, numerals 40,46 and 300 represent input terminals; 47 and 41 represent outputterminals; 302 represents destination terminal address request messagetransmission means; 303 represents destination address detection means;304 represents a control circuit; 305 represents a timer; 306 representsdestination terminal address non-capture message generation means; 307represents a switch; 310 represents destination terminal address requestmessage detection means; 311 represents a comparator; 312 represents aself terminal name capture means; and 313 represents transmission means.The ad hoc/ infrastructure network identification means 65 starts up thedestination address detection means 303 in response to a start-up signalinput via the input terminal 300. A destination terminal name issupplied to the destination terminal address message requesttransmission means 302 and the destination address detection means 303via the input terminal 46. The destination terminal address messagerequest transmission means 302 configures the destination terminaladdress request message containing the destination terminal name as abroadcast packet for all terminals connected to the ad hoc network. Thedestination terminal address message request transmission means 302outputs the broadcast packet to the output terminal 41 via thetransmission queue 313 and a timer start-up pulse to the timer 305 tostart up the timer 305. The destination address detection means 303extracts a destination terminal address response message from thereceive packet input via the input terminal 40 and detects an addresscorresponding to a destination terminal address name a receive packetsupplied via the input terminal 46. Then the destination addressdetection means 303 outputs the detected address to the switch 307 whileit outputs an address detection pulse representing address detection tothe timer 305 and the control circuit 304. The timer 305 is reset inresponse to an address detection pulse. When the timer 305 becomes atime-out after start-up, a time-out pulse representing a time-out isoutput to the control circuit 304 and the destination terminal addressnon-capture message generation means 306. The control circuit 304controls the switch 307 to output a message showing that the destinationterminal address input from the destination terminal address non-capturemessage generation means 306 cannot be captured and an output from thedestination address detection means 303, to the output terminal 47. Thedestination address request message detection means 310 detects adestination address request message in response to a receive packet fromthe input terminal 40 and then extracts a terminal name of which adestination address is required. The comparator 311 receives a terminalname from the destination address request message detection means 310and a self terminal name. When the terminal name is equal to the selfterminal name, the comparator 311 starts up the destination addressmessage transmission means 314. The destination address messagetransmission means 314 creates a destination address message containingthe terminal name and the terminal address of a self terminal and thenoutputs the transmission queue 313 to transmit a broadcast packet onto acommunication medium.

The ad hoc/ infrastructure network identification means 65 shown in FIG.4 can be configured as shown in FIG. 6. Referring to FIG. 6, numeral 40represents an input terminal; 94 to 96 represent output terminals; 97represents infrastructure network advertisement message receive means;98 represents ad hoc network advertisement message receive means; 27 aand 27 b represent counters; 34 represents a timer; 91 and 92 representcomparators; and 93 represents decoder. In response to an input packet,the infrastructure network advertisement message receive means 97detects an infrastructure network advertisement message containing thenetwork address of a network connected to the mobile terminal and thenoutputs a message detection pulse to the counter 27 a. In response to aninput packet, the ad hoc network advertisement message receive means 98detects an ad hoc network advertisement message containing the networkaddress of a network connected to the mobile terminal and then outputs amessage detection pulse to the counter 27 b. The counter 27 a counts upevery time the message detection pulse is input and then receives areset pulse when the timer 34 become time-out. The counter 27 b countsup every time the message detection pulse is input and then receives areset pulse when the timer 34 become time-out. In response to a resetpulse, the counter 27 a outputs the count number of message detectionpulses at the reset time to the counter 91. In response to a resetpulse, the counter 27 b outputs the count number of message detectionpulses at the reset time to the counter 92. The comparator 91 comparesthe input signal with zero and then outputs a pulse representing zero orother value. The comparator 92 compares the input signal with zero andthen outputs a pulse representing zero or other value. When thecomparator 91 outputs a pulse representing that the input signal is notzero, as a pulse starting up the infrastructure network destinationaddress capture means 66, to the output terminal 94. When the comparator92 outputs a pulse representing that the input signal is not zero, as apulse starting up the infrastructure network destination address capturemeans 64, to the output terminal 95. The decoder 93 receives the signalfrom the comparator 91 and the signal from the comparator 92. When thecomparator 91 outputs a pulse representing that the input signal is notzero, the decoder 93 outputs a control signal to the switches 61 and 65to selectively output an output from the infrastructure networkdestination address capture means 66 and outputs a control signal to theswitch 61 to output an input signal to the infrastructure networkdestination address capture means 66. When the comparator 92 outputs apulse representing that the input signal is not zero, the decoder 93outputs a control signal to the switches 61 and 65 to selectively outputan output from the ad hoc network destination address capture means 64and outputs a control signal to the switch 61 to output an input signalto the ad hoc network destination address capture means 64.

The infrastructure destination address capture means 66 shown in FIG. 4can be realized using the domain network system that inquires a terminaladdress corresponding to a destination terminal name and then notifiesthe mobile terminal inquired by a server of the destination terminaladdress (refer to Douglas E. Comer, “Internetworking with TCP/IP VolumeI Principles, protocols and architecture”, Third edition, 1995,Prentice-Hall, Inc.).

The ad hoc/ infrastructure network integration address management means45 shown in FIG. 1 can be configured a shown in FIG. 7. Referring toFIG. 7, numeral 40 represents an input terminal; 41 represents an outputterminal; 102 represents infrastructure network address managementmeans; 103 represents ad hoc network address management means; 104represents ad hoc/ infrastructure network integration identificationmeans; and 105 represents a switch. Based on the receive packet from theinput terminal 40, the ad hoc/ infrastructure network integrationnetwork identification means 104 starts up the ad hock networkmanagement means 103 when the mobile terminal is connected to an ad hocnetwork and starts up the infrastructure network management means 102when the mobile terminal is connected to an infrastructure network. Thead hoc/ infrastructure network integration network identification means104 selects the output from the ad hoc network address management means103 or infrastructure network address management means 102 in a start-upstate by controlling the switch 105 and outputs it tot he outputterminal 41.

The ad hoc/ infrastructure network identification means 104 shown inFIG. 7 can be configured as shown in FIG. 8. Referring to FIG. 8,numerals 40 represents an input terminal; 21, 22, and 24 representsoutput terminals; 25 represents infrastructure network advertisementmessage receive means; 26 represents ad hoc network advertisementmessage receive means; 27 a and 27 b represent counters; 28, 29 and 30represent comparators; 31 represents a decode; 32 represents an encoder;33 represents an adder; and 34 represents a timer. A receive packet isinput to the infrastructure network advertisement message receive means25 and the ad hoc network advertisement message receive means 26 via theinput terminal 40. When the infrastructure network advertisement messagereceive means 25 detects an infrastructure network advertisementmessage, it outputs a message detection pulse to the counter 27 a. Whenthe ad hoc network advertisement message receive means 26 detects an adhoc network advertisement message, it outputs a message detection pulseto the counter 27 b. The counter 27 a counts up every time the messagedetection pulse is input while it receives a reset pulse output when thetimer 34 becomes time-out. The counter 27 b counts up every time themessage detection pulse is input while it receives a reset pulse outputwhen the timer 34 becomes time-out. In response to the reset pulse, thecounter 27 a outputs the count number of message detection pulses at thereset time to the comparator 28 and then resets the count number. Inresponse to the reset pulse, the counter 27 b outputs the count numberof message detection pulses at the reset time to the comparator 28 andthen resets the count number. The adder 33 adds the output from thecounter 27 a and the output from the counter 27 b and outputs the sum tothe comparator 29. Each of the comparators 28, 29 and 30 compares aninput signal with zero and then outputs a pulse representing whether ornot the input signal is zero. The comparator 28 the pulse to the outputterminal 21 and the decoder 31. The pulse from the output terminal 21representing that the input signal is not zero is output as a start-upsignal for the infrastructure network address management means 102. Thecomparator 29 outputs the pulse to the decoder 31 and the encoder 32while the comparator 30 outputs the pulse to the decoder 31 and theencoder 32. The decoder 31 outputs a control pulse to the switch 105.The control pulse means that (1) the infrastructure network addressmanagement means 102 outputs its output to the output terminal 41 whenthe decoder 31 receives a pulse representing that the input signal isnot zero, from the comparator 28, that (2) the ad hoc network addressmanagement means 103 outputs its output to the output terminal 41 whenthe decoder 31 receives a pulse representing that the input signal iszero, from the comparator 29, and that (3) the ad hoc network addressmanagement means 103 outputs its output to the output terminal 41 whenthe decoder 31 receives a pulse representing that the input signal isnot zero, from the comparator 30. The encoder 32 receives output pulsesfrom the omparators 29 and 30, encodes (1) a signal representing a newad hoc network configuration when the decoder 32 receives a pulserepresenting that the input signal is not zero from the comparator 29and (2) a signal representing a pulse configuration showing connectionto an existing ad hoc network when the decoder 32 receives a pulserepresenting that the input signal is not zero from the comparator 30,and then outputs the encoded signal as a start-up pulse to the ad hocnetwork address management means 103 to the output terminal 24.

The infrastructure network address management means 102 captures theterminal address of the mobile terminal and the network address of theinfrastructure network. This can be realized by, for example, thedynamic host configuration protocol (DHCP) (for example, refer toDouglass E. Comer, “internetworking with TCP/IP Vplume I Principles,protocols and architecture”, Third edition, 1995, Prentice-Hall, Inc.).In the DHCP, a DHCP server is installed that manages terminal addressesand network addresses on an infrastructure network to supply a terminaladdress and a network address based on a request of the mobile terminal.

In contrast, the ad hoc network address management means 103 shown inFIG. 7 can be configured as shown in FIG. 9. Referring to FIG. 9,numerals 40 and 115 represent input terminals; 11 represents an outputterminal; 112 represents ad hoc network/ terminal address managementmeans; 113 represents ad hoc network/ network address management means;and 114 represents a transmission queue. Each of the ad hoc network/terminal address management means 112 ad the ad hoc/ network addressmanagement means 113 receives receive packets via the input terminal 40for management operation. The ad hoc network/ terminal addressmanagement means 112 outputs messages for management to the transmissionqueue 114, thus sending it to the switch 105 via the output terminal111. The ad hoc network/ network address management means 113 outputsmessages for management to the transmission queue 114, thus sending itto the switch 105 via the output terminal 111. Each of the ad hocnetwork/ terminal address management means 112 and the ad hoc network/network address management means 113 receives a signal representingwhether or not the output terminal 24 (shown in FIG. 8) is connected toa newly configured ad hoc network, or is connected to the existing adhoc network. The ad hoc network/ network address management means 113outputs a network address of an ad hoc network to be connected and anetwork address captured signal showing network address capturecompletion to the ad hoc network/ terminal address management means 112.

The ad hoc network/ network address management means 113 shown in FIG. 9is configured as shown in FIG. 10. Referring to FIG. 10, numerals 115and 40 represents input terminals; 113, 131 and 134 represent outputterminals; 121 represents ad hoc network/ network address requestmessage detection means; 122 represents ad hoc network advertisementmessage detection means; 123 represents ad hoc network/ network addresscapture means; 124 represents a gate; 125 an 126 represent switches; 127represents a memory; 128 represents a comparator; 129 represents ad hocnetwork/ request network address spent message message transmissionmeans; and 133 represents a transmission queue. The decoder 132 decodesan input signal sent via the input terminal 115. As a result, when theinput signal represents new ad hoc network configuration, the decoder132 starts up the ad hoc network/ network address capture means 123 andcontrols the switches 125 and 126 to select the output from the ad hocnetwork/ network address capture means 123. When the system is connectedto the existing ad hoc network, the decoder 132 starts up the ad hocnetwork advertisement message detection means 122 and controls theswitches 125 and 126 to slet the output from the ad hoc networkadvertisement message detection means 122.

Let us now explain the case where the system is connected to an existingad hoc network. The ad hoc network advertisement message detection means122 is started up. Then the ad hoc network advertisement messagedetection means 122 receives a receive packet input via the inputterminal 40, detects an ad hoc network advertisement message containingthe network address of an ad hoc network, and extracts the networkaddress of the ad hoc network. The mobile terminal is connected to thenetwork using the network address. The switch 126 sends the networkaddress to the output terminal 134 and the memory 127. The switch 125sends a network address captured signal representing that a networkaddress has been captured, to the gate 124 and the output terminal 131.In response to the network address captured signal, the gate 124 passesthe output of the ad hoc network/ network address request messagedetection means 121. The ad hoc network/ network request messagedetection means 121 receives a receive packet via the input terminal 40.When a new ad hoc network is configured, the ad hoc network/ networkrequest message detection means 121 detects an ad hoc network/ networkaddress request message and then extracts a required network address.The ad hoc network address request message contains a desired networkaddress and is broadcast onto the communication medium. The requirednetwork address passes through the gate 124. The comparator 128 comparesthe requested network address with the ad hoc network address of thecurrently-connected ad hoc network stored in the memory 127. When thenetwork address agrees with the network address stored in the memory127, the ad hoc network/ request network address spent messagetransmission means 129 is started up to transmit as a broadcast packetan ad hoc network/ request network address spent message representingthe network is in use. The ad hoc network/ request network address spentmessage transmission means 129 configures an ad hoc network/ requestnetwork address spent message and then outputs it to the transmissionqueue 114 via the transmission queue 133 and the output terminal 130.

Next, explanation will be made as to the case where a new ad hoc networkis configured. In this case, the ad hoc network/ network address capturemeans 123 starts up. The ad hoc network/ network address capture means12 shown in FIG. 10 can be realized as shown in FIG. 11. Referring toFIG. 11, numerals 500 and 40 represent input terminals; 503, 510 and 511represent output terminals; 502 represents network address candidatesetting means; 503 represents ad hoc network/ network address requestmessage transmission means; 504 represents ad hoc network/ networkaddress captured signal detection means; 506 represents ad hoc network/request network address spent message detection means; 507 represents acomparator; 508 represents a timer; and 509 represents a gate. Thenetwork address candidate setting means 502 receives a signal from thedecoder 132 via the input terminal 500 and then outputs the networkaddress candidate of an ad hoc network to be configured while it startsup the timer 508. The ad hoc network/ network address request messagetransmission means configures an ad hoc network/ network address requestmessage using the input network address candidate and then outputs it asa broadcast packet to the transmission queue 133 to transmit onto thecommunication medium via the output terminal 511. The ad hoc network/request network address spent message detection means 506 receives apacket on the communication medium via the input terminal, detects an adhoc network/ request network address spent message, and then extracts aspent network address to output to the comparator 507. The comparator507 compares the spent network address from the ad hoc network/ requestnetwork address spent message detection means 506 with a network addresscandidate from the network address candidate setting means 502. If boththe addresses are agreed, the comparator 507 re-starts up the networkaddress candidate setting means 502 and then outputs a different networkaddress as a network address candidate. At this time, the networkaddress candidate setting means 502 restarts up the timer 508.

The time-out of the timer 508 means that an ad hoc network/ requestnetwork address spent message of the network address candidate as aspent network address is not received within the measurement time of thetimer 508. The network address candidate is used as the network addressof a new ad hoc network. Thus, when the timer 508 becomes a time-out, atime-out signal is output to the gate 509 and the ad hoc network/network address captured signal generation means 504. In response to thetime-out signal, the gate 509 opens to output as a captured networkaddress the network address candidate from the network address candidatesetting means 502 to the switch 128 via the output terminal 511. The adhoc network/ network address captured signal generation means 504outputs a network address captured signal to the switch 125 via theoutput terminal 503.

The ad hoc network/ terminal address management means 112 shown in FIG.9 can be configured as shown in FIG. 12. Referring to FIG. 12, numerals115, 198, 199 and 40 represent input terminals; 159 represents an outputterminal; 150 represents ad hoc network/ terminal address capture means;151 represents a control circuit; 152 and 153 represent memories; 154represents a gate; 155 represents ad hoc network/ terminal addressrequest detection means; 156 represents ad hoc network/ terminal addresslist detection means; 157 represents ad hoc network/ terminal listtransmission means; 158 represents a comparator; and a transmissionqueue. The ad hoc network/ terminal address capture means 150 receives asignal from the output terminal 24 via the input terminal 115, a networkaddress captured signal from the output terminal 134 via the inputterminal 199, a capture network address from the output terminal 131 viathe input terminal 199; and a packet sent from the input terminal 40.The transmission queue 160 receives a necessary message as a broadcastpacket transmits to the transmission queue via the output terminal 159.When capturing a terminal address, the ad hoc network/ terminal addresscapture means 150 outputs a terminal address captured signal to thecontrol circuit 151 and a terminal address list to the memory 152. Whenreceiving a terminal address captured signal, the control circuit 151opens the gate 154 while it stores the open time into the memory 153.

When the gate 154 opens after the capture of the terminal address, thereceive packet from the input terminal 40 is input to the ad hocknetwork/ terminal address request detection means 155 and the ad hocnetwork/ terminal address list detection means 156. When detecting an adhoc network/ terminal address list request message requesting theaddress list of a terminal connected to the ad hoc network, the ad hocknetwork/ terminal address request detection means 155 starts up the adhoc network/ terminal address list transmission means 157 to startstransmitting the address list held. At the startup, the ad hoc network/terminal address list transmission means 157 configures as a broadcastpacket an address list stored in the memory 152 and an address network/address list message containing the address list based on the time theterminal is connected to the network and then outputs it thecommunication medium via the transmission queue 160. When receiving anad hoc network/ terminal address list message containing the addresslist, the ad hoc network/ terminal address list detection means 156halts the operation of the ad hoc network/ terminal address listtransmission means 157 while it extracts the address list from areceived message. Then, the address list is output to the comparator158. The comparator 158 compares the received address list with theaddress list held in the memory 152. The address list in the memory 152is updated based on the comparison list.

The ad hoc network/ terminal address capture means 150 shown in FIG. 12can be configured as shown in FIG. 13. Referring to FIG. 13, numerals115, 131 (198), 134 (199) and 40 represent input terminals; 175, 178 and179 represent output terminals; 183 and 182 represent logical productcircuits; 171 represents a gate; 181 represents a decoder; 180represents,ad hoc network/ terminal address setting means; 174represents ad hoc network/ terminal address list request messagetransmission means; 172 represents ad hoc network/ terminal address listmessage detection means; 173 represents ad hoc network/ terminal addressselection means; and 177 and 178 represent switches. A signal is inputfrom the output terminal 24 via the input terminal 115. The decoder 181outputs a start-up pulse to the logical product circuit 182 when a newad hoc network is configured and outputs a start-up pulse to the logicalproduct circuit 183 when the mobile terminal is connected to theexisting ad hoc network. The logical product circuit 183 obtains thelogical product of the network address captured signal input via theinput terminal 170 and the output of the decoder 181. The logicalproduct circuit 182 obtains the logical product of the network addresscaptured signal input via the input terminal 170 and the output of thedecoder 181. When both the signal from the decoder 181 and the signalfrom the input terminal 198 are input, the logical product circuit 183starts up the ad hoc network/ terminal address list request messagetransmission means 174 to connect the mobile terminal to the existing adhoc network. When both the signal from the decoder 181 and the signalfrom the input terminal 198 are input, the logical product circuit 182starts up the ad hoc network/ terminal address setting means 180.Moreover, by controlling the switches 176 and 177, the decoder 181outputs the output from the ad hoc network/ terminal address selectionmeans 173 when the mobile terminal is connected to the existing ad hocnetwork and outputs the output from the ad hoc network/ terminal addresssetting means 180 when a new ad hoc network is configured.

First, the ad hoc network/ terminal address setting means 180 is startedup and then captures the terminal address in the new ad hoc network. Thead hoc network/ terminal address setting means 180 receives a networkaddress to be used in the new ad hoc network, from the output terminal134 via the input terminal 199. Since there are no other terminals inthe ad hoc network, the ad hoc network/ terminal address setting means180 decides a terminal address based on the network address from theinput terminal 199. Moreover, an address list is output based on apredetermined address. The switch 176 outputs the address list to thememory 152 via the output terminal 179. When the address list is output,the switch 177 outputs a terminal address capture signal showingterminal address capture to the control circuit 151 via the outputterminal 178.

When the mobile terminal is connected to the existing ad hoc network,the ad hoc network/ terminal address list request message transmissionmeans 174 is started up. The ad hoc network/ terminal address listrequest message transmission means 174 creates an ad hoc network/terminal address list request message requiring a terminal address listconnected to the ad hoc network and then outputs it as a broadcastpacket on the communication medium via the output terminal 175, thustransmitting it to the transmission queue 160. At this time, the gate171 passes a receive packet input from the input terminal 170. The adhoc network/ terminal address list message detection means 172 receivesa receive packet from the input terminal 40 and then detects an ad hocnetwork/ terminal address list message containing as a message anaddress list. The ad hoc network/ terminal address list messagedetection means 172 extracts an address list from the message andoutputs it to the ad hoc network/ terminal address list selection means173. The ad hoc network/ terminal address list selection means 173selects an address not still used from the input address list as theterminal address of the mobile terminal, enters it into the addresslist, and then outputs it to the memory 152 via the switch 176 and theoutput terminal 179. The terminal address capture signal showing theterminal address capture is output to the control circuit 151 via theswitch 177 and the output terminal 178.

The ad hoc network/ terminal address list transmission means 157 shownin FIG. 12 can be configured as shown in FIG. 14. The ad hoc network/terminal address list transmission means 157 employs the mobile terminalcontrol method (procedure of providing information) according to thethird aspect of the present invention. Referring to FIG. 14, numerals200, 203, 205 and 208 represents input terminals; 202 represents anoutput terminal; 201 represents ad hoc network/ terminal address listmessage creation means; 204 represents current time capture means; 206represents time difference derivation means; and 207 represents a timer.In response to the start-up signal from the ad hoc network/ terminaladdress request detection means 155 via the input terminal 200, the adhoc network/ terminal address list message creation means 201 receivesan address stored in the memory 152 from the input terminal 203 and thencreates an ad hoc network/ terminal address list message, thus startingup the current time capture means 204. The current time capture means204 captures a current time and outputs it to the time differencedeviation means 206. The time difference deviation means 206 receivesthe current time and a terminal address capture time stored in thememory 153 via the input terminal 205 and derives the time for which theterminal is connected to the ad hoc network, thus outputting it to thetimer 207. The timer 207 determines the measurement time based on theconnection time derived from the time difference deviation means 206.The timer 207 receives a process halt signal output from the ad hocnetwork/ terminal address list detection means 156 via the inputterminal 208. In response to the process halt signal, the timer 207 isreset. The timer 207 notifies the ad hoc network/ terminal address listmessage creation means 201 of its time-out. When receiving notificationof the time-out from the timer 207, the ad hoc network/ terminal addresslist message creation means 201 outputs a created ad hoc network/terminal address list message to the transmission queue 160 via theoutput terminal 202 to transmit as a broadcast packet onto thecommunication medium.

According to the present invention, the mobile terminal can integrallymove between an infrastructure network and an ad hoc network.

Moreover, according to the present invention, the mobile terminalcontrol method (method of providing information) can effectively providenecessary information for communications.

The entire disclosure of Japanese Patent Application No. 9-210995 filedon Aug. 5, 1997 including specification, claims, drawing and summary areincorporated herein by reference in its entirety.

What is claimed is:
 1. A method of controlling a mobile terminal,comprising the steps of: providing information to a first mobileterminal connected to an ad hoc network, which is a temporary networkconfigured of only plural terminals, wherein another mobile terminalstarts up a random timer in response to an information request from amobile terminal, wherein said random timer allows only a terminal whichhas a first time-out of the random timer to supply information over thead hoc network; controlling a mobile terminal by another mobileterminal, wherein upon detection of a time-out of the random timer by adetecting mobile terminal, the detecting mobile terminal broadcasts aninformation supply message which ceases the random timer of each of themobile terminals which have started up a random timer.
 2. A mobileterminal controlling method including a procedure of providinginformation to a mobile terminal, said mobile terminal being connectedto an ad hoc network which is a temporary network configured of onlyplural terminals, comprising the steps of: a. broadcasting aninformation requesting message to all mobile terminals connected to saidad hoc network by means of a first mobile terminal connected to an adhoc network; b. starting up a random timer by means of each of saidmobile terminals configuring said ad hoc network which receives saidinformation requesting message, said random timer measuring a randomtime; c. broadcasting an information supply message corresponding tosaid information requesting message to all mobile terminals connected tosaid ad hoc network by means of a mobile terminal in which time-out ofsaid random timer has occurred among mobile terminals which have startedup said random timer; d. ceasing said random timer when each of saidmobile terminals which have started up said random timer receives saidinformation supply message and then stopping said information supplymessage from being transmitted.
 3. A method of controlling a mobileterminal, comprising the steps of: providing information from a terminalwith a shortest ad hoc network connection time when information isprovided to a first mobile terminal connected to said ad hoc network,which is a temporary network configured of only plural terminals; andcontrolling a mobile terminal by another mobile terminal, wherein upondetection of a time-out of the random timer by a detecting mobileterminal, the detecting mobile terminal broadcasts an information supplymessage which ceases the random timer of each of the mobile terminalswhich have started up a random timer.
 4. A mobile terminal controllingmethod including a procedure of providing information to a mobileterminal, said mobile terminal being connected to an ad hoc networkwhich is a temporary network configured of only plural terminals,comprising the steps of: a. broadcasting an information request messageto all mobile terminals connected to an ad hoc network by means of afirst mobile terminal connected to said ad hoc network; b. determiningan ad hoc network connection time based on a time connected to said adhoc network and a time at which said information requesting message hasbeen received, by means of each of mobile terminals configuring said adhoc network which has received said information request message; c.starting up a timer that measures a time according to a period of timefor which a mobile terminal is connected to said ad hoc network; d.broadcasting a response message corresponding to said informationrequesting message when time-out of said timer has occurred, and ceasingsaid timer; and e. halting said timer when a response message isreceived to said information requesting message during an operation ofsaid timer.